Readings

Box-and-arrow models of cognition

The box and arrow slides described a logical process of taking symptoms and, by searching for double dissociations, building a model of modules (boxes) and connections (arrows) that can explain all the patient data. The goal is to get a good model of how that behavior is normally accomplished. Concepts of association, double dissociation, and the symptoms that force us to propose distinct processing systems (boxes) and conduits of information between them (pathways or wires).

The genetics of reading

A dual route model of reading was described: this is a modular or box and arrow diagram based on clinical behavior. It suggests that words are normally processed both via a lexical route (which is based on a store of whole words), and by a sub-lexical route, which is based on processing the sounds that letters make

In the lecture, I explained work translating this box and arrow cognitive model into genetic terms and examined using twins to see if the different modules are influenced by genes

It was argued that there are genes for the lexical and non-lexical processes. Some candidate areas that might contain these genes were then mentioned.

Study Plan

There is only one exam question on my section of the course

You can think of the lectures as providing a general framework for describing cognition: boxes and arrows, then building a box-and arrow model of language based on symptoms from patients like Bramwell's, and for reading, where I relate the model to genetic influences on the cognitive modules.

In preparing for the exam, you should learn the models of language and reading presented, paying attention to symptoms. Feel capable to draw those models and explain why the boxes and arrows are necessary. More ambitiously, you might try and map the results of the genetic model mapped onto the boxes and arrows. Is reading affected by genes? Are some genes limited to just a single box or process?

FAQ

How exactly are genetic studies related to the dual route cascade model and the genetic model or reading?

At a simple level, they reveal that genes tell the same story as patients: They are therefore like a new source of patients for double dissociation studies

What do the decimal numbers in the genetic model or reading represent?

The numbers are path coefficients: correlations between a factor and a behaviour, like reading.

Do we have to know the names of all the genes involved in reading and diagnosing dyslexia and their different effects on neural function?

You don't have too, but learning [wikipedia: Rote_learning facts] often helps recall and understanding. The effects might be relevant for thinking about why one might want to know what genes do to understand a behavior.